Marvell International Limited

Marvellworld Trade Ltd.

Atul Salhotra

Kedar Shirali

Hui-Ling Lou

Rohit U Nabar

Hongyuan Zhang

Zhiyu Yang

Bhaskar Nallapureddy

Sergey Timofeev

Sudhir Srinivasa

Arul Durai Murugan Palanivelu

Brian Bosso

Sandesh Goel

Timothy J Donovan

Yungping Hsu

Ken Kinwah Ho

Swaroop Venkatesh

Chia-Chun Chung

Tam Tran

Harish Ramamurthy

Ravi Narasimhan

Xiayu Zheng

Rahul Kopikare

Ken Yeung

Thomas B Cho

Todd Wheeler

Srinivasa H Garlapati

Kevin Hsiao-Cheng Tang

Riddhi Madani

Erik Heinke

Yakun Sun

Li Zhang

Songping Wu

Mao Yu

Qing Zhao

Raphael Cendrillon

Li Lin

Bo Wang

Hemabh Shekhar

Srinivas Pinagapany

Ping Gao

A method of calibrating analog transceiver delay includes generating a signal in a portion of a first device to arrive at a first known time at analog transmit circuitry of the first device, transmitting the signal from the analog transmit circuitry of the first device, receiving the transmitted signal, and deriving transceiver delay from the received signal. The transmitting may be performed via a closed loop to analog receiver circuitry of the first device, detecting the signal at a second known time at an output of the analog receiver circuitry of the first device. The transmitting also may be performed wirelessly to receiver circuitry of a second device placed at a predetermined distance from the first device, detecting the received signal at a second known time at the receiver circuitry of the second device. Transceiver delay can be determined from transit time and apportioned between transmit delay and receive delay.

Method and apparatus for calibrating transmit delay and receive delay

Systems and techniques relating to processing multiple data streams include, according to at least one implementation, receiving a single bit stream during a SISO mode of transmission; receiving two or more bit streams during a MIMO mode of transmission, wherein different rotations are applied to dynamically changed second, third, and fourth ones of the two or more bit streams received during the MIMO mode of transmission to improve transmission robustness and transmission data rate; performing separate de-mapping of subcarriers in the two or more bit streams during the MIMO mode of transmission; performing separate de-interleaving of the two or more bit streams during the MIMO mode of transmission, wherein a first portion of a de-interleaver section that handles a first of the two or more bit streams employs a same de-interleaver operation as during the SISO mode of transmission; and combining the two or more bit streams.

Data stream interleaving with different rotations applied to changed bit streams for spatially diverse transmission

A device including a first transceiver configured to transmit and receive, using a first antenna, according to a first communication protocol, a second transceiver configured to transmit and receive, using a second antenna, according to the first communication protocol, and a third transceiver configured to transmit and receive, using the second antenna, according to a second communication protocol. A controller is configured to select between a first mode where the first, second, and third transceivers are configured to respectively communicate using the first and second antennas at a same time, and a second mode where the first, second, and third transceivers are configured to respectively communicate using the first and second antennas at different times. In the first mode and the second mode, the controller is further configured to selectively allow the second transceiver to transmit and receive using the second antenna at a same time as the third transceiver.

Systems and methods for selecting between coexistence modes in a wireless device

Systems and methods for removing DC offset from a signal are provided. A radio frequency signal is received at a receiver. The radio frequency signal is converted into a digital signal including a periodic component with a period. A carrier frequency offset is removed from the digital signal to generate a frequency-shifted digital signal. The frequency-shifted digital signal is filtered to remove a DC offset in the digital signal. The filtering includes applying a moving average filter matched to the period to remove the periodic component from the frequency-shifted digital signal. The moving average filter generates a set of average values based on the frequency-shifted digital signal. The filtering also includes taking a difference between consecutive values of the set of average values to determine the DC offset, where the DC offset is introduced at the receiver.

Systems and methods for DC offset correction

A first sounding packet is transmitted from the wireless communication device to a calibration station. A first channel descriptor is generated based on the first sounding packet. A second sounding packet is transmitted from the calibration station to the wireless communication device. A second channel descriptor is generated based on the second sounding packet. The first channel descriptor and the second channel descriptor are obtained at a processor device. Calibration coefficients indicative of one or both of phase imbalance and amplitude imbalance between a receive radio frequency (RF) chain and a transmit RF chain at the wireless communication device are generated based on the first and the second channel descriptors. The calibration coefficients are sent from the processor device to the wireless communication device.

Wireless device calibration for implicit transmit beamforming

Devices and methods capable of addressing filter responses are disclosed. For example, a method for compensating a first low-pass filter and a second low-pass filter is disclosed. The method includes injecting a reference tone fand a cutoff tone finto the first low-pass filter, and measuring respective filter responses of the reference tone fand the cutoff tone fwhile changing capacitor codes that control a cutoff frequency of the first low-pass filter until a first capacitor code Iis determined that most accurately causes the first low-pass filter to utilize a desired cutoff frequency f, performing a similar operation for the second low-pass filter until a second capacitor code Qis determined, and calibrating for mismatch between the first low-pass filter and the second low-pass filter.

Methods and systems for calibrating an analog filter

Systems and techniques relating to processing multiple data streams include, according to at least one implementation, an apparatus including a parser for a MIMO mode; an interleaver section coupled with the parser, configured to perform separate interleaving of bit streams during the MIMO mode, wherein a first portion of the interleaver section that handles a first of the two or more second bit streams employs a same interleaver operation as during a SISO mode of transmission; a subcarrier mapping section configured to perform separate mapping of subcarriers during the MIMO mode; and a transmit back end coupled with the subcarrier mapping section to connect with multiple antennas, the transmit back end configured to apply different rotations to dynamically changed second, third, and fourth ones of the two or more second bit streams transmitted over the multiple antennas during the MIMO mode to improve transmission robustness and transmission data rate.

Data stream interleaving with different rotation applied to changed bit streams for spatially diverse transmission

In a method of calibrating a wireless communication device, a first sounding packet is transmitted from the wireless communication device to a calibration station. A first channel descriptor is generated based on the first sounding packet. A second sounding packet is transmitted from the calibration station to the wireless communication device. A second channel descriptor is generated based on the second sounding packet. The first channel descriptor and the second channel descriptor are obtained at a controller. Calibration coefficients indicative of one or both of phase imbalance and amplitude imbalance between a receive radio frequency (RF) chain and a transmit RF chain at the wireless communication device are generated based on the first and the second channel descriptors. The calibration coefficients are sent from the controller to the wireless communication device.

Wireless device calibration for implicit transmit

A transceiver utilizes a spatial spreading matrix to distribute two or more encoded spatial data streams to multiple antennas. The spatial spreading matrix satisfies one or more of the following two constraints: (a) the ratio of squared norms of the sum of the components of a row, for different rows of the spatial spreading matrix, is equal to a first constant sequence, and (b) the ratio of squared norms of the sum of a symbol Sto be transmitted, when the symbol Sis equal to 1 or &#x2212;1, multiplied by each of the components of a row, for different rows of the spatial spreading matrix, is equal to a second constant sequence.

Equal power output spatial spreading matrix for use in a wireless MIMO communication system

Systems and methods are provided for suppressing interference from a received data signal. A characteristic of a channel is estimated, the channel being configured for transmission of data between a transmitting device and a receiving device having two or more receive antennas. A spatial correlation of interference is determined for the two or more receive antennas based on the channel characteristic. The received data signal is filtered based on the spatial correlation.

Systems and methods for suppressing interference in a wireless communication system

A system including a physical layer module and a control module. The physical layer module is configured to generate a first clear channel assessment for a first sub-channel of a communication channel and generate a second clear channel assessment for a second sub-channel of the communication channel. The first clear channel assessment indicates whether the first sub-channel is free or busy. The second clear channel assessment indicates whether the second sub-channel is free or busy. The control module is configured to, in response to the second sub-channel being busy, extend a duration of the second clear channel assessment by a predetermined period of time, and transmit data via (i) only the first sub-channel or (ii) both the first sub-channel and the second sub-channel based on (a) the first clear channel assessment, (b) the second clear channel assessment, and (c) the extended duration of the first clear channel assessment.

Opportunistic 40 MHz mode of transmission in wireless transmitters

Systems and techniques relating to processing multiple data streams include, according to an aspect, a method including interleaving data streams to be transmitted over a wireless channel, wherein the interleaving comprises performing a first permutation and a second permutation, and applying data rotations to the data streams in connection with the interleaving, wherein each of the data rotations has a constant rotation value for its corresponding stream index regardless of how many data streams are currently being transmitted, a second rotation value used for a second stream is larger than a first rotation value used for a first stream, a third rotation value used for a third stream is greater than the first rotation value but less than the second rotation value, and a fourth rotation value used for a fourth stream is greater than the second rotation value, and wherein the data rotations are applied after the second permutation.

Data stream interleaving with non-monotonically arranged data rotations for spatially diverse transmission

A wireless network device comprising a physical layer (PHY) module and a media access control (MAC) module. The PHY module is configured to communicate with an 80 MHz channel. The 80 MHz channel includes a plurality of sub-bands including a first sub-band, a second sub-band, a third sub-band, and a fourth sub-band. One of the plurality of sub-bands corresponds to a primary channel. The PHY module is further configured to determine which of the plurality of sub-bands are receiving a data packet, and generate at least one clear channel assessment signal indicating which of the plurality of sub-bands are receiving the data packet. The MAC module is configured to receive the at least one clear channel assessment signal from the PHY module, and selectively transmit on the primary channel based on the at least one clear channel assessment signal.

Coexistence mechanism for 802.11AC compliant 80 MHz WLAN receivers

A network station includes a sampling device configured to generate samples of radio frequency activity on a medium. A first correlator is configured to autocorrelate the samples based on a first delay to generate a first autocorrelation value. The first delay matches periodicity of a jam signal. The jam signal indicates a second station is to transmit data. The second station is separate from the network station. A second correlator is configured to autocorrelate the samples to generate a second autocorrelation value. The second autocorrelation value indicates whether the radio frequency activity includes periodic noise. A controller is configured to prevent the network station from transmitting a radio frequency signal on the medium based each of the first autocorrelation value and the second autocorrelation value.

Method and apparatus for preventing a first station from transmitting a signal onto a medium in response to the first station detecting interference on the medium

A bias current utilized in a unit of a radio frequency (RF) receiver device of a network interface is controlled. A modulation scheme utilized in a packet being received by the network interface is determined. It is determined, based on the determined modulation scheme, whether a level of the bias current should be changed. When it is determined that the level of the bias current should be changed, a control signal to change the level of the bias current is generated.

Growing community of inventors

Sunnyvale, CA, United States of America

Atul Salhotra